Dr. Carl Bell was waiting his turn to check in at his hotel. A well-regarded psychiatrist and academic, he was traveling for a television appearance. The TV station had flown him first-class and sent a chauffeur-driven car to pick him up at the airport. But just before he stepped up to speak with the hotel clerk, a white man marched in and cut him off. Bell, who is black, was indignant.

"Do you think I'm waiting for a bus?" He demanded. "I'm standing right here!"

The man claimed he simply hadn't seen him.

To many, this would seem to be an ambiguous encounter. Perhaps the man had not seen Bell waiting in line. But to Bell, it was part of a pattern -- one he says he sees virtually every day. The sheer number of negative interactions has convinced him, and many others, that they are more than innocent oversights.

Indeed, social scientists have coined a term for them: racial microaggression. The phrase describes the subtle indignities and insults directed at minorities during everyday exchanges. Their ambiguity is what makes them so vexing -- the recipient doesn't know for certain whether a slight is deliberate, making it difficult to know how to react.

Racism, both overt and subtle, has been a feature of human interaction for centuries. But now that blatant public displays of prejudice are frowned upon -- and even criminalized -- the more subtle manifestations are receiving increased attention from researchers. By giving this phenomenon a name, social scientists hope to draw attention to how damaging such slights can be when multiplied by the thousands of times they may occur over a lifetime.

"I see a huge irony," said Derald Wing Sue, professor of education at Columbia University's Teachers College. "While hate crimes receive the most attention, the greatest damage to the life experiences of people of color is from racial microaggression."

'Invisible, but potentially lethal'

While the term "microaggression" is relatively new, the concept is familiar enough that it has become a staple of contemporary comedy. Take Steve Carell's character, Michael Scott, on NBC's popular situation comedy "The Office." As the boss of the branch office for a paper company in Scranton, Pa., Scott unwittingly offends his employees at every turn.

In one typical episode, Scott rejects the need for diversity training, claiming the office is a "color-free zone." He then turns to the only black employee and says, "Stanley, I don't look at you as another race."

Or Larry David, whose eponymous character on HBO's "Curb Your Enthusiasm" is always offending someone with his colossal insensitivity. In the current season, the premise that David and his wife have taken in a black family left homeless by a hurricane is grist for scores of uncomfortable racial encounters.

"It is funny," said Bell of this genre of humor. "But that's what humor is, that fine line between funny and tragic."

"Microaggression" was coined in 1970 by Harvard psychiatrist Chester Pierce to explain the indignities heaped on black people, sometimes unknowingly, by whites. It has since been broadened to include all minority groups and women.

Columbia's Sue, who has become a leading scholar on the topic, compared these insults to carbon monoxide -- "invisible, but potentially lethal." Because the comments or gestures are easily overlooked, the experts say, their effect may not be immediately apparent. But constant negative interactions can be a sort of death by a thousand cuts for the victim.

Sue outlined the various types of microaggression perpetrated on different races. Asian-Americans may find themselves answering the question "Where were you born?" over and over again, when in fact they were born in the United States. Sue, who is Asian-American, said people regularly compliment him on how well he speaks English.

"I hope so," he replies. "I was born here."

Collusion?

Some psychologists say focusing on microaggression is the wrong approach.

It's nearly impossible to divine the meaning of some remarks, said psychologist and consultant Kenneth Sole. Although his diversity seminars explore subtle racism, Sole said, he avoids the word "microaggression."

"I don't use that term, because it's based on the false assumption that we understand the motivations of those surface, micro behaviors," he said.

When people who hear these comments presume that racism is the motivation, he added, they forestall any further communication. The resulting power dynamic of aggressor and victim ultimately makes the recipient feel even worse. In choosing the explanation that makes us feel the most uncomfortable, "we are colluding with the people who wish to victimize us," Sole said.

Those who study microaggression agree that eliminating it is an uphill battle. Some are trying to use the university environment as a laboratory for discovering ways to combat it. Hiring a diverse faculty and educating professors about cultural sensitivity are some of the steps they recommend.

Bell said that while human behavior is complex and "multidetermined," the vast majority of bias has the same roots. "Ninety-eight percent of racial stereotyping," he said, "is learned behavior."

Jessica Troiano is a master's candidate at Columbia University Graduate School of Journalism.

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